Carbureter.



I PATENTED MAR. 26, 1907. C. O HEDSTROMQ OARBURBTER. APPLI0ATI40N FILEDJULY 14. 1905.

' To all whom it may concern.-

CARL -o. HEDSTROM, 0F SPRINGFIELD, MASSACHUSETTS.

CARBURETE'R.

Specification of Letters Patent.

Patented March 26, 1907.

, Application filed July 14,1905. Serial No. 269,747.

Be it known that I, CARL O. HEDSTROM, a citizen of the United States ofAmerica, residing at Springfield, in the county of Hampden and State ofMassachusetts, have invented new and useful Improvements in Carburetorsof which the following is a specification.

This invention relates to carbureters such as are adapted for use inconnection with internal-combustion engines for the purpose of supplyingthereto the combustible element-s wit sue a proportionate-admixture ofair as to ermit the combustion thereof to be effecteri under the mostfavorable conditions; and the articular object of the invention is toprovi e a carbureter for this purpose havin the characteristic of whatis known as exibility. In explanation of this term in the sense in whichit is used in this application it should be stated that as at presentgenerally constructed, in the carbureters which are used for theatomization or volatilization of a liquid fuel (which is that generallyemplo ed in internal-combustion en,- gines) a re ated supply of fuel isdelivered from a nozzle located in an air-passage one end of which isopen to the atmosphere and the other of whic is connected with the'cylinder of the engine, the suction effect of the piston drawing airthrough the carburcter' serving to draw from the nozzle the requiredsupply of combustible in the form of-a spray or vapor, which min lingwith the air'passes on to the engine. in throttling down the engine ifthe area of the air-passage through the carbureter be contracted ,orexpanded the volume of air which can be drawn therethrough' on thesuction-stroke'will of course be varied, but there will be no variationof the area of the supply-nozzle. By thus varying the area ofsaidassage-wa the velocity of the air moving t rough sai passage-way willvary. Therefore there will be a varianozzle, the result being avariation in he proportion of combustible to a given vol ume of air. Ifthe supply of combustible be increased or diminished, whereby the speedof the piston is varied, the'suction effect of the piston likewisevaries according to variation of the piston speed. A flexible carbureterthe sense used herein is therefore. one which may be ad usted to normalconditions of operation of the engine, but in which ameter of the lowerend under abnormal conditions.(as, for example, when it is desired to;run the engine either above or below its normal speed) the volume of theair will be automatically increased or diminished relative to thequantity of the combustible. The invention is clearly illustrated in theaccompanying drawings, in which- .Figure 1 is an elevation, artly insection, of a carbureter to which tlie'invention has been applied. Fig.2 is a diagrammatic view illustrating the action of the air when thelatter is moving through the carbureterat relatively low velocity. Fig.3 is a similar view to Fig. 2, showing the action. of the air' when itis moving through the carbureter at a relatively high velocity. Fig. 4is a perspective view of that part of a carbureter to which theinvention is applied.

It is to be noted that the particular form or type or carbureter shownin the drawings accompanying this application forms no part of theinvention whatever, and it lS'SlIOWIl herein merely as illustrative of acarbureter embodying t 1e general fei ttures ofnearly all carburetersm'so far as the vaporizing or atomizlng action thereof is concernedwhere'- by the fuel is mixed with an.

For the 'purpose of this application, however, it may, be

considered that 0. indicates an air-passagethrough the carburetor,having an inlet 1;

open to the atmosphere and an outlet-open-.

lug c, which through a suitable pipe (I is con-' nected with thecylinder of an internal-combustion'enginc. In this passage is anatomizing-nozzle e, located at the end of a pipe f, which extends intothe air-passa e a, preferably axially thereof, said pipe being connectedwith a suitable reservoirg, containing liquid fuel, so arranged that'tlie'fu'el will be maintained at a corstant level somewhat below theoliliceoi'ihe ntomizing nozzle, as usual in this class of constructions.

The air-passage a at that point immediately surrounding the fuel-supplynozzle is preferably circular in crcss-sectiqi, and Fig.

4 shows this feature, this figureillustratiii -ae cylindricalmemberjr'of the carburetei located in the nip-passage therethrough andformiu a part thereof and in which the atoniizuig-nozzle is located, theinternal diof this cylindrical member; less the space t icrcin occupiedby the,axially-located atoinizing nozzle, deter- :5 this rib n, the coilbeing soldered to the inner .wall; of said part 7', as shown in thevarlous a,

' engine slows down to a certain degree below.

mining the maximum diameter of a column of air which may be drawntherethrough on a full suetion stroke of the engine. v The essentialfeature of 'this invention consists in applying to the internal wall ofthat part of the member h a rib m, which extends inwardly from saidwalland preferably is in the form of a continuous spiral extending frombelow to a point above the ori- Io fice of the atomizing-nozzle.

It has been determined in practice that a wire in the form of a coilwith relatively wide spaces "between theconvolutions thereof is one ofthe most convenient ways of applying figures of the drawing. Thisconstruction, however, is to be-undei'stood merely as the preferredembodiment of the invention, and, if desired, the inwardly-extendin ribm may be applied to or formed on the wall of the airpassage surroundingthe atomizing-nozzle in any way; i g In operation it hasbeengleterminedthat 2 5 when the'engine is run below its maximum speedand the velocity of the column of air moving through the carbureter' istherefore below the maximum the capacity of the airpassage through thatpart of the carbureter which is-occupied bythe inwardly-extending rib mis determined by the area thereof measured from the inner edge of therib m on oneside to the inner edge thereof on the other, this actionbeing clearly illustrated in Fig. 2-, 3 5 in which the diameter of theair-current is.

indicated by lines 0 0. In other 'words, the inwardly-extending ribswill choke said. air-passage to the extent of their inward extensionfrom the walls of the part j when the the normal speed. This slowingdown of the engine implies, obviously, the need of less fuel, and areduction of the quantity of fuel implies, of course, a smaller volumeof air 4 5 with which it is to mix if the relativepri'iportions of 'airand fuel are to be maintained.

, On the other hand, when the engine is running at its maximum orsomewhat above its normal speed the suction ellect produced by thequicker stroke of the piston will cause the column of air drawn throughthe air passage at a higher velocity to move through the/part "tionhaving an air-passage therethrough and "a sp1rallydisposed rib securedto the inner j of the air-passa e in a more or less spiral path, asindicator in Fig. 3, which will per' 5 5 mit it to fill saidainpassagethrough the part 7' to the extent of the entire diameter thereofmeasured from .one wall to the other, and

- thereby enlarging the capacity of the air-passage at that point to theextentof the inward extension of the rib m into said passage, and

tending above and below the delivery-orifice the volume of air which maybe drawn through the part j of the air-passage when a *highers eed isrequired is cowse-quentl greater t an will be delivered through the gsame passage at a lower speed, and the greater i velocity of the airwill draw a larger quantity of fuel from the nozzle e. Furthermore,

.the spiral movement of the air around the supply-nozzle operates toeffect the delivery .of flexibility above referred to, which is essential to the production of a uniformly-burning combustible mixture.

Having thus described my invention, what I claim, and desire to secureby Letters Patent of the United States, is- I 1. A carbureter consistingof a body ortion having an air-passage therethroug a fuel-supplynoz'zlein saidpassage, and a s iral rib extending for a short distance from t emlet end of said body portion into said passage, at an angle to the axisthereof, the spiral rib being secured to the inner wall of the bodyportion and circular in cross-section whereby the inlet area of the bodyunder normal suction is reduced, and under abnormal suction isincreased.

2. A carbureter: consisting of a body por- 9 tion having an air-passagetherethrough, a fuel-supply nozzle axially arranged in said passage withrelation to the body portion,

and spirally arranged ribs in the passage whereby the effectivecross-sectional areaiof said passage will be varied by a variation ofthe velocity of the aircurrent moving through said passage. v 3. Acarburetor consisting of a body porwall of the air-passage and extendinginto said passage at an angle to the axis thereof, whereby the effectivearea of the air-passage depends upon the velocity of air there'- through.4'. ,A carbureter consisting of a body having'an air-passagetherethrough, a fuel- IIO supply nozzle in said passage,a rib spirallydisposed on the inner wall of said passageat an angle to the axisthereof, said rib occu-. pying a comparatively small ortion only of theair-passage when considered transversely of the axis of the body.

. 5. A carburetor consisting of ,a body having an airpassage"therethrough, a fuel supply nozzle in saidpassage and c0ncen-- triowith the airpassage, a rib spirally dis-v posed on the inner wall of thelatter and ex- 1 2 5 of said nozzle, therib occupying a small portiononly of the, air-passage when considered tral'isverscly of its axis.

6. A carburetor consisting of a body having an air-passagetherethrough,a fuel-sup: 13o

f s esgrz o ply nozzle arranged in the axis of theair 7', vA carbureterconsisting of a body 'portion having an air-passage therethrough, aspirally-disposed rib on the interior portion of the air-passage andadjacent the outlet of the fuel-supply but leavin a freeunobstruct-edpassage-way between t esame and the fuelsupply nozzle. 8[ In acarbureter of the class described, a body portion-having an airpassageextending therethrough, a supply located 1 5 in the air-passage, a siral rib on the interior ofthe air-passage an I e'xtendin toward theaxis of the airpas'sage-Way but eav'ingafre'e unobstructed passage-waytherethrough be- -tween the ribv and the fuel-sup ly whereby a 20 rotaryefiect' proportional to t e velocity of air is given tothe fueladmixture of air and iq t CARL o. HEDsTRoM.

Witnesses: i i

WM. H. GHAPIN, K. I; CLEMoNs.

